The Islet Cell Biology Core Laboratory of the DRTC is responsible for the islet biology functions that were originally provided by the Cellular and Molecular Biology and Genetic Studies Core Laboratory. We have instituted this new core in response to the increased demands for pancreatic islets and for methods for characterizing islet function in normal and mutant animals. We feel that these services are best provided by a dedicated core rather than being a function of another core. This Core will provide independently funded investigators with rodent and human pancreatic islets from normal and diabetic animals for their studies. It will also maintain insulinoma cell lines for distribution. The Core will also provide service and training in methods for studying islet and beta-cell biology including insulin secretion, immunohistochemistry of insulinand other hormone-seereting cells, and calcium imaging and other biophysical methods for studying pancreatic islet and beta-cell function. Dr. Louis Philipson will serve as Director and Dr. Donald Steiner will serve as Co-Director.